Electric-circuit closer.



J. A. KENNEDY-MOGREGOR ELECTRIC CIRCUIT CLOSER. APPLICATION FILED APR.2, 1910.

991,853. Patented May 9, 1911.

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J. A; KENNEDY-MoGRBGOR. ELECTRIC CIRCUIT CLOSER.

APPLICATION FILED APR. 2, 1910.

Patented May 9, 1911.

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UNITED STATES PANT FFTQE.

JOHN ALEXANDER KENNEDY-MoGREG-OR, OF BIRMINGHAM, ENGLAND, ASSIGNOR 0FONE-HALF T0 EDWARD WILLIAM BONSON, OF KNOWLE, ENGLAND.

ntnc'rnic-cincuir CLOSER. I

Specification of Letters Patent.

Patented May 9, 1911.

Application filed April 2, 1910. Serial No. 553,090.

To all whom it may concern:

Be it known that 1, JOHN ALEXANDER KENNEDY-MGGREGOR, a subject of theKing dom of Great Britain, residing at 27 5 Slade road, Gravelly Hill,Birmingham, in the county of \Varwick, England, engineer, have inventedcertain new and useful Improvements in or Relating to Electric-CircuitClosers, of which the following is a specification.

This invention comprises an improved electric circuit closer or starterfor use in connection with motors and for other pur poses and it relatesto the class wherein the contact bar successively engages with a se riesof contact studs in the process of switching the resistances out ofcircuit with the motor armature. If the resistances are cut out toorapidly the armature is liable to be damaged and various devices havebeen suggested for limiting the speed at which the attendant is able tooperate the contact arm.

According to the present invention the contact arm is coupled to a mainor operating arm in such a manner that excessive pressure applied to thelatter by the operator in the process of operating the starter, effectsthe disconnection of the contact arm and frees it from the control ofthe main arm. Upon a gradual movement of the main arm however theoperating device is enabled to maintain its engagement with the contactarm until the whole of the resistances are cut out. It will beunderstood that the operator is not only constrained to cut out theresistance gradually but cannot damage the apparatus in an attempt toaccelerate-the movement of the starter by undue force.

Referring to the drawingsFigure 1 is a front elevation of a circuitcloser or starter constructed in accordance with the presentimprovements showing the apparatus in the open position. Fig. 2 is aside view of the device shown in Fig. 1. Fig. 3 is a fragmentary planshowing the operative connection between the main and contact arms. Fig.1 shows in perspective view the operative connection between the mainand the contact arms.

In a convenient embodiment of this invention such as illustrated by thedrawings the piston a of the dash pot A is coupled to an arm B which ispivotally connected as at C to the main and contact arms D, E, the saidarm B being normally inclined at approximately 90 to the main andcontact arms when the starter is in the open position shown in Fig. 1.The operating device upon the main arm D is pivoted and coupled with aspring plunger f which carries a roller f, such roller f being retainedin contact with the arm B to which the dash pot A is coupled, thearrangement being such that upon a gradual movement being imparted tothe main arm. D the dash pot is closed by the spring plunger the latterremaining stationary in relation to the main arm. Should however themain arm be operated too rapidly the spring f of the plunger iscontracted by the dashpot, and the operating device d thereby moved fromengagement with the detent 6 upon the contact arm E, such operatingdevice d being in the shape of a bridle and pivotally attached at d tothe main arm D. The plunger f is extended and enlarged to form atransverse eye f for articulation to the operating device. g g areguides for the said plunger, the upper one g constituting an abutmentfor the spring while 9 is a collar on the plunger Upon contraction ofsuch spring in the man ner aforesaid the plunger moves in relation tothe main arm D and thereby through the eye f and its pivot swivels, thepart (5 and lifts the transversely extending portion which engages thedetent c out of engagement therewith. Both the operating device cl andthe detent c are provided with inclined faces (Z 6 so that upondisengagement the main arm D may again be readily engaged with thecontact arm E and stops it h are provided at the pivot of arm D and uponarm B so arranged that the dash pot is opened and the contact armreturned upon the main arm being replaced to the open position.

What I claim as my invention and desire to secure by Letters Patentis 1. A circuit closer of the character described, comprising incombination with the operating lever of a controller, a contact armnormally coupled to said lever, an arm having one of its ends pivotallyconnected to the lower end of said contact arm, a dash pot having itspiston coupled to the other end of said arm, and means to disengage saidcontact arm from the operating lever for the purpose of preventing anabrupt movement of the contact arm from its open to the closed position,substantially as described.

2. A circuit closer of the character described, comprising incombination with the operating lever of a controller, acontact armnormally coupled to said lever, an arm having one of its ends pivotallyconnected to the lower end of said contact arm, a dash pot having itspiston coupled to the other end of said arm, and a spring controlledplunger guided upon the operated lever, a roller upon the lower end ofsaid plunger, kept in contact with the upper face of said arm, a detentupon the contact arm, and an operating device pivotally secured to theop erating lever, normally engaging with its inclined face the inclinedface of said detent, and adapted to be disengaged therefrom by thecontraction of the spring controlling the movement of said plunger,substantially as I described and for the purpose set forth.

3. A circuit closer of the character described, comprising incombination with the operating lever of a controller, a contact armnormally coupled to said lever, an arm having one of its ends pivotallyconnected to the lower end of said contact arm, a dash pot having itspiston coupled to the other end of said arm, and a spring controlledplunger, guides for the same upon the operated lever, the upper guideforming an abutment for one end of the spring encircling said plunger,and controlling its movement, a collar upon said plunger forming an abutment for the lower end of said spring, a detent upon the contact arm, anoperating device pivotally secured to the operating lever, normallyengaging with its inclined face the inclined face of said detent, an eyeupon the upper end of said plunger, adapted to disengage and readilyengage said detent and operating device, stops upon the pivot of thearms, and upon arm to regulate the relative movements of said arms, andmeans to operate said plunger, substantially as described and for thepurpose set forth.

In witness whereof I have hereunto set my hand in the presence of twowitnesses.

JOHN ilLEXANDER KENNEDY-MUGREGOR. Witnesses ROWLAND L. GooLD, l/ViLLIAMA. DAVIS.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, I). C.

